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EvoStevo
08-25-2009, 12:30 PM
So I guess this goes here. As many of you know, I'm planning on swapping a D24T into my 245. While I'm at it, I figure I may as well upgrade the turbo as well. With a bit of help from this forum and others I hope to have the turbo put together by winter. Here're the parts I've gathered so far:

http://i72.photobucket.com/albums/i173/Lightning_KP61/DSC_0336-1.jpg
So here are the two compressors side by side. On the left we have a Hitachi HT-18 from a 2nd gen Mazda RX7. The housing is supposed to be .60 A/R but I have no idea what the wheel trim is. On the right is a Garrett (AiResearch) T3 out of an old turbo diesel Mercedes. The compressor housing A/R is .42, which I believe is the stock size for the D24T. I plan on using the Hitachi compressor housing and wheel.

http://i72.photobucket.com/albums/i173/Lightning_KP61/DSC_0339-1.jpg
Here are the two turbine housings. The Garrett is on the left and the Hitachi is on the right. The Garrett housing is nearly identical to the one found on the D24T but a bit larger at .48 A/R. The Hitachi housing is enormous (supposedly a 1.0 A/R) and has a twin scroll design, but as Slobodan said in the "More power" thread it has a non-standard flange, so I'll obviously be using the Garrett housing for my project.

http://i72.photobucket.com/albums/i173/Lightning_KP61/DSC_0340-1.jpg
Here you can see the oil-only CHRA and wastegate actuator of the Garrett. I'm still not entirely sure how the wastegate works as there's no arm that I can see. Maybe someone can explain it to me.

http://i72.photobucket.com/albums/i173/Lightning_KP61/DSC_0342-1.jpg
Here we have the oil- and water-cooled CHRA from the Hitachi. I'd really like to use this one so I can prolong the life of the turbo and stretch out my oil change intervals. Also, when I finally get to the veggie conversion, I figure the extra heat in the coolant coming out of the turbo will help heat up my vegetable oil tank faster. Not sure if it works that way or if I can even get the CHRA to play nicely with the Garrett turbine housing, but it made sense in my head.

There you have it. The extent of my frankenturbo plans. This will be my first time taking apart and reassembling a turbo so I'd love to hear some suggestions from you all.

EvoStevo
08-25-2009, 12:34 PM
http://i72.photobucket.com/albums/i173/Lightning_KP61/DSC_0293.jpg
I might as well throw this one in as well. Here's a pic that I snapped awhile back of the ebay intercooler I plan to use. My setup will be more or less a clone of 500dollar744ti's on turbobricks (documented here: http://forums.turbobricks.com/showthread.php?t=131057).

Jason
08-27-2009, 07:19 PM
The watercooled center section probably wont make much difference, as the diesel turbos dont run as hot as the gasser ones do, its not needed. I don't suppose it would hurt, but that would be a bunch of extra plumbing in an already cramped area. I think the combo of the .60 compressor and the .48 exhaust will work nicely, but that exhaust housing isn't the greatest. I would keep searching around for a standard style housing like most T-3 turbos have. That factory waste gate has a actuator rod that goes straight down into the housing, and the end is shaped like a valve (think regular engine intake or exhaust valve). The turbo on my Jetta diesel was the same waste gate type, I think they did it because of space restrictions. The whole assembly is much more compact against the turbo compaired to most.

Jason

EvoStevo
08-28-2009, 11:52 AM
The watercooled center section probably wont make much difference, as the diesel turbos dont run as hot as the gasser ones do, its not needed. I don't suppose it would hurt, but that would be a bunch of extra plumbing in an already cramped area. I think the combo of the .60 compressor and the .48 exhaust will work nicely, but that exhaust housing isn't the greatest. I would keep searching around for a standard style housing like most T-3 turbos have. That factory waste gate has a actuator rod that goes straight down into the housing, and the end is shaped like a valve (think regular engine intake or exhaust valve). The turbo on my Jetta diesel was the same waste gate type, I think they did it because of space restrictions. The whole assembly is much more compact against the turbo compaired to most.

Jason

Oh, is coking not a problem for turbo diesels? I knew that diesels didn't run as hot as gassers, but wasn't sure if heat was still a problem for the oil. I was also planning on getting an EGT probe and gauge just so I could keep an eye on exhaust temps. Should I skip it though?

I think I'm going to stick with this turbine housing for now. If a cheap one from a 280ZX or Ford 2.3T comes up (I think those are both .48 with standard T3 flanges) then I'll get it. Is there a way to test if the wastegate actuator will hold pressure? Does the diaphragm or spring ever wear out or need to be replaced?

Jason
08-28-2009, 02:54 PM
The diaphram goes bad, as mine did. If you just put some shop air to it, you should be able to see the waste gate valve open up. Coking is only a problem if you shut it down hot (like right after running the crap out of it). Just let it idle for a minute to cool. EGT probe would be a good idea if you plan to really throw some fuel at it.

Jason

Slobodan
11-15-2009, 07:29 PM
So how goes this project?
I am working on using the Mercedes .48 Turbine with my Hitachi compressor. And with the stock center section. Or maybe just tap the oil inlet for the appropriate threads. Either way, I am looking forwards to the upgrade in turbine size.

Slobodan
11-15-2009, 07:47 PM
Okay, I am drunk... but thats how I get motivated :)


I took both turbine housings off the TurboDiesel VW turbo setup and The Turbo Diesel Mercedes turbo setup. and swapped them.... the turbine wheels both seems identical to me, but the housings them selves are different. the .36 is smaller visually and the .48 mercedes is noticeably larger. but the wheels are infact the same size. .12 difference between the two due the housings physical size difference. That makes my upgrade seem very easy any probably not that noticeable..... Or would it? how many of you think it would be? because sooner or later I would be doing this. I do have two more negra modelo's in my fridge. I might be inspired to do it in the dark.. out side.. but then I can't drive.. because I have been driving. fvck... hmm.. I'll wait.

IceV_760
11-16-2009, 12:41 AM
Nice project, first time i notice this somehow.
Jason already told how wastegate without noticeable "arm" works.
Sad i cant really much help you to choose your turbo, but ill
watch and give other comments, keep going!

Jason
11-16-2009, 04:29 AM
I wouldn't bother changing the hot side to the larger .48 a/r as it will be a higher rpm before it spools. I would upgrade the compressor side to move more air. I would only change the hot side when you really start to push some fuel and boost and need more flow. I am told the stock exhaust housing flows very well, but at some point it is going to become restrictive.

Jason

Slobodan
11-16-2009, 10:05 AM
Well, I have been aiming for keeping my cruising boost level lower. My wagon has the 373:1 rear end ratio... so doing 70mph in OD is 3000 rpms about. that also means I'm constantly pushing 5psi or so just to maintain that speed. but I know I don't need it.. so this is why I am leaning towards the slightly larger turbine housing.

EvoStevo
11-16-2009, 12:25 PM
Hey guys, it's been awhile. I haven't started on the turbo project yet. I actually haven't done anything with my cars for the last three months or so as work has been so busy. My 240 is just sitting for right now until I find the time to work on it again, but once it's running I can concentrate on the turbo. I'll probably just stick to my original plan and do the .60/.48 T3 minus the water-cooled center section. Hopefully I'll have an update for you soon.

Jason
11-16-2009, 12:33 PM
Mine is also right at 3000rpm at 70, and on level ground thats probably good for 3 to 4 lbs of boost with my even bigger .63 A/R. Granted, my compressor housing is much bigger so even though my turbine speed is slower, its pushing more air. It may not really reduce the cruising boost all that much. I wouldn't really worry about a few lbs of boost on the highway. 5lbs under a light throttle isn't taxing the engine, and is just keeping all the fuel burnt and everything clean.

Jason

Slobodan
11-24-2009, 01:28 AM
Well I did it, I changed out the .36 Turbine housing with the Mercedes .48 turbine housing tonight, and yeah, there is a difference! Right at about 2,800 rpms its climbing up to 6psi and the power just pours on, like its scooting along briskly. and that about where boost just about rockets to 10psi and stays. much different for me than the .36 which didn't do that. it just slowly and steadily went to 10psi... maybe there was something wrong with its wastegate?

I also did a bit of much needed maintenance ---> timing belt, front main seal, and water pump. the belt was fraying where the teeth meet the low spot on almost every tooth. On the bottom timing belt cover and trough were covered with timing belt remnants because of the oil leak that sprang up in July.

I was very very very glad I finally got to it!!!

IceV_760
11-24-2009, 02:42 AM
Nice to hear Slobodan.
Tell us more about the driveability of the car in normal use?

Slobodan
11-24-2009, 07:32 PM
Normal driving seems fine. The mercedes turbine is still the same basic design as the stock turbine but bigger .48 A/R.

Ultimately I would want to get a .48 A/R or .63 A/R Gasser Garrett Volvo 240 style turbine housing on my existing center and compressor (.60 A/R HT18) or T4 .70 A/R compressor. Hmm.. Ultimately.

But Its kind of fun to do that whole step by step way... Just so see what changes I make result in the way I get power from my setup.

Jason
11-24-2009, 07:45 PM
So you only changed the turbine housing at this point, and still running the stock compressor side? I would say the waste gate was either starting to open too soon or was leaking. The .36 housing should have made the boost skyrocket right up to 10 lbs no problem. The slightly more lazy spool up to 6 or so would be what I would expect with the larger .48 housing. Either way, if your happy with the result and it improved performance, than it was worth it. Wait till you upgrade the weeny compressor side! You think it spools hard now... Have you turned up the pump much?

Jason

Slobodan
11-24-2009, 09:23 PM
I had all ready changed the out the .42 Compressor.... done that 1 month after I completed the swap last spring `09. As of now I've got a .48/.60 T3.

Its strange, I've noticed with the stock Turbos VW vs Mercedes.
That on the VW we've got the .36 with the .42 and the compressor. seems okay.
On the Mercedes we've got the .48 with the .42 compressor. however the inlet tapers down a bit before the compressor wheel.. Same as SAAB turbo 900's I've noticed. So whats up with the Differences? obviously bigger is better and smaller sucks.

Jason
11-27-2009, 05:57 AM
Different trim compressor wheels and different designed housings. Some of the shape may be for sound. The HE351 found on the later common rail cummins engines have a "silencer ring" that pretty much necks down right before the compressor wheel to keep the whistle down. Its one of the first things to go if your looking up turn up the power.

Jason

Jason
11-27-2009, 05:58 AM
If it spooled slowly like you were saying with the larger compressor side already, and the stock .36 exhaust, there must have been a waste gate problem. It should have really spooled well with the larger comrpessor and stock exhaust housing.

What have you done to your pump if anything?

Jason

Slobodan
11-27-2009, 06:26 PM
I've constantly messing with the pump, I've got it timed to .88 now. I like it better there I think. before it was clicked in at .95. runs smoother now. and as for fuel I'm trying to just get it set moderately. I am not trying to wild there. My goals for this car is not extreme. but not stock.

kevinyoung03
01-01-2010, 12:33 AM
I also think the same. There is no requirement of this and you can do of your own.